Excavator tool comprising a support, an auger mounted rotatably

ABSTRACT

An excavator tool comprising an auger rotatable in a support by a motor, the motor being coupled to the auger through a vibration-generator which will impose a variable rotation on the auger over the rotation imposed by the motor, the generator including a ram coupled to the motor or its shaft and to the auger drive shaft, eccentrically relative to one of them at least. A regulator controls feed of fluid to the working chamber of the ram and discharge of fluid therefrom.

United States Patent [1 1 Leyrat et al.

[ EXCAVATOR TOOL COMPRISING A SUPPORT, AN AUGER MOUNTED ROTATABLY [75] Inventors: Pierre Jean leyrat, Trilport; Didier Albert Wolf, Meaux, both of France [73] Assignee: Societe Anonyme: Poclain, Le Plessis Belleville, France [22] Filed: Feb. 25, 1974 [2|] Appl. No.: 445,263

[30] Foreign Application Priority Data Mar. 12, I973 France 73.08723 [52] US. Cl. 173/163; 173/49 [5|] lnt. Cl. E21B 3/02 [58] Field of Search 173/163, 49; 175/56; 259/DIG. 43

[56] References Cited UNITED STATES PATENTS 3,3l9,723 5/1967 Kramer l73/l63 X [451 Sept.9, 1975 Hettich et al. .i l73/l63 X Kato l73/49 X Primary Examiner-David H. Brown Attorney, Agent, or FirmLewis H. Eslinger; Alvin Sinderbrand 5 7 ABSTRACT An excavator tool comprising an auger rotatable in a support by a motor, the motor being coupled to the auger through a vibration-generator which will impose a variable rotation on the auger over the rotation imposed by the motor, the generator including a ram coupled to the motor or its shaft and to the auger drive shaft, eccentrically relative to one of them at least. A regulator controls feed of fluid to the working chamber of the ram and discharge of fluid therefrom.

3 Claims, 8 Drawing Figures PATENTEDSEP QIY-S sum 1 o 3 EXCAVATOR TOOL COMPRISING A SUPPORT, AN AUGER MOUNTED ROTATABLY This invention is concerned with excavator tools and more particularly augers.

The techniques hitherto known for producing cylindrical holes in the ground employ an auger and cxer tion on the auger of a continuous action compounded of an axial bearing force and a rotational torque.

The considerable friction on the surface of the tool and the tamping effect in the region of the head of the tool necessitate the application of considerable forces.

It is obvious and it has been proved that the output obtained from this method is poor. It has therefore appeared wise to actuate the tool with a vibratory motion of moderate amplitude, especially in rotation, the movement becoming superimposed on the helicoidal motion of penetration.

The object of the present invention is to provide an improved continuous-motion auger.

According to the present invention there is provided an excavator tool comprising a support, an auger mounted rotatably with respect to the said support, a motor for driving the auger in rotation, linked between the support and the auger, and a vibration-generator interposed between the support and the auger, which in operation generates a vibratory rotational motion coaxial with the main rotation of the auger, the generator comprising a fluid-operable ram having at least one working chamber, and means for placing the chamber alternately in communication with a source of fluid under pressure and with a discharge tank, the ram being linked between one of the relatively movable elements of the motor, the frame or the output shaft, which is movable with respect to the support, and the shaft of the auger, and eccentrically with respect to at least one of these parts comprising the movable element of the motor and the shaft of the auger.

In a preferred embodiment a regulator effects the alternate communication of the working chamber and comprises a central hub linked to the movable element of the motor and inserted in a sleeve fixed with respect to the support of the tool. When the ram has one working chamber, two apertures are arranged in the inner face of the sleeve and are connected, the first to the source of fluid under pressure, and the second to the discharge tank, whilst a duct is bored into the hub, which opens in the course of a rotation of one revolution of the hub with respect to the sleeve, during one portion of this rotation into the first aperture and during another portion of the said rotation into the second aperture, and is connected to the said working chamber.

When the ram is of the double-acting type and has on this account a second working chamber, another duct is advantageously bored into the hub, which opens permanently into the first aperture and is connected to the said second working chamber.

The invention will be better understood and its secondary characteristics as well as their advantages will appear in the course of the description of one embodiment, given below by way of example, in which reference will be made to the accompanying drawing, in which:

FIG. I is an elevation of an embodiment of tool in accordance with the invention;

FIG. 2 is a partial axial section of the tool shown in FIG. 1',

FIG. 3 is an axial section similar to that of FIG. 2 but illustrating the detail of the vibration-generator; this Figure is moreover a section along the line III-ll] in FIGS. 5, 6 and 7;

FIGS. 4, 5, 6 and 7 are sections respectively along lines lVlV, VV, Vl-VI and VII-VII of FIG. 3; and

FIG. 8 illustrates the diagram of a hydraulic circuit for control of the vibrator-generator illustrated in FIG. 3.

The tool illustrated in FIG. 1 comprises a support 1 fixed with respect to the ground and comprising, for example, the end beam of a public works machine. A flange 2 is hinged on support 1 by means of ears 3 integral with the flange and a connector pin 4. A housing 5 of a hydraulic motor is attached by bolts 6 to the flange 2, a flange 5a of the housing 5 being arranged for this purpose which abuts flange 2. Another housing 8 shielding a vibration-generator and furnished with a flange 9 is connected with the housing 5 of the motor by means of bolts 10 and of a second flange 5b of the housing 5 abutting the flange 9.

From the housing 8 projects an intermediate shaft I2 which, it will be seen later, is linked in rotation to the output shaft of the hydraulic motor, the housing of which has been referenced S. A flange 13 on the intermediate shaft I2 is made fast by bolts 14 with a flange 15 of shaft 16 of an auger 11. In addition, there is to be observed the presence of two parts of fluid pipes:

pipes 17 and 18 connected on the one hand to the motor in the housing 5 and on the other hand respectively to a source of fluid under pressure and to a discharge tank, and

pipes 19 and 20 connected on the one hand to the vibration-generator and on the other hand respectively to a source of fluid under pressure and to a discharge tank.

Referring to FIGS. 2, 3 and 4, it will be observed that the intermediate shaft 12 is mounted rotatably in the housing 8 by means of roller bearings 21 whilst a seal 22 is interposed at the outlet of the housing 8 between the said shaft and the said housing. A plate 23 is fast with the intermediate shaft 12 and is furnished with a lug 24 arranged offset with respect to axis 25 of the shaft 12.

Furthermore, a plate 26 is locked rotationally to the output shaft 27 of the motor in the housing 5, by means of driving splines 28. A sleeve 29 is fixed to the housing 8 by means of a bolt 30, whilst the pipes 19 and 20 are connected to this sleeve 29. A lug 31 is fixed to the plate 26, being arranged on this plate offset with respect to the axis of rotation of the said plate which coincides with the axis 25. It will be seen that a doubleacting ram 32 is linked by its rod 33, articulated about the lug 24, to the plate 23 and by its cylinder 34, articu lated about the lug 31, to the plate 26. Two flexible connector pipes 35 and 36 are connected on the one hand to the two chambers of the ram 32 and on the other hand to two ducts 37 and 38 respectively, bored in the plate 26.

Referring more especially to FIG. 3, it is to be observed that a hub 39 is integral with the plate 26 and is mounted rotatably in and with a seal against a bore 290 in the sleeve 29. The shaft 27 and the hub 39 are maintained axially locked by a bolt 40. The ducts 37 and 38 extend into the hub 39 and emerge through ducts 37a, 38a and 38b facing the bore 29a in the sleeve.

In the course of one revolution of the hub 39 with respect to the sleeve 29, the ducts 37a, 38a and 3819 are put in selective communication with the apertures 41, 42 and 43 arranged in the sleeve 29 and opening into the bore 29a. Thus it will be observed in reference to FlG. 5 that the aperture 43 extends over an angular sector less than half a revolution, the duct 38b is axially at its level, and the pipe is connected to this aperture 43. Referring to FIG. 6 it will be observed that the aperture 42 extends over an angular sector less than half a revolution and the duct 38a is axially at the same level. Further, the angular sectors of the apertures 42 and 43 are substantially diametrically opposed. Finally, FIG. 7 shows that the aperture 41 extends over the whole of the circumference, the duct 37a opens permanently into this aperture 41 and likewise the pipe 19 is connected to the aperture 41. Again, it is to be made clear that while the apertures 41, 42 and 43 are axially offset, the apertures 41 and 42 are permanently in communication with one another as may be seen in H6. 3.

On the diagram in FIG. 8 are reproduced various elements already described above. It is to be observed that a regulator 44 consisting in this instance of the assembly of the sleeve 29 and the hub 39 is linked to the motor with the housing 5. The pipes and 36 are connected respectively to the chambers of the ram 32, of small working section 32b and large working section 320. The regulator 44 has two positions which are alternately selected in the course of the rotation of the shaft of the motor in the housing 5 and which correspond, one to the putting in communication of the pipes 19 and 36, 38, the other to the putting in communication of the pipes 36, 38 and 20. Furthermore, the chamber 32b is permanently in communication with the pipe 19, through the pipes 35, 37 and 370.

It is likewise to be noted that a pump 46 is connected by its suction pipe 47 to a tank 48 and by its delivery pipe to the inlet of the motor with the housing 5. A pipe 49 tapped off from the pipe 45 connects that pipe to the tank 48, a calibrated discharge valve 50 being arranged in this pipe 49. A pipe 51 connects the delivery from the motor in the housing 5 to the tank 48. Finally, it is to be observed that an adjustable constriction 52 of a type similar to that illustrated, for example, in regard to FIG. 6 of the French Pat. No. 72 ()6 315 of Feb. 24, 1972, is arranged in the pipe 45.

With the explanation of the functioning of the tool which has been described, the advantages to be derived from its employment will be better understood.

Referring first of all to the diagram in FIG. 8 and observing the similarity of the means combined to those of the devices described in the French Pat. No. 72 06 315 aforesaid, it is easily understood that the piston rod 33 of the ram 32 is going to be animated with a vibratory motion, the frequency of which may be adjusted, in particular, by modifying the adjustment of the constriction 52. The jack 32 therefore constitutes a vibration-generator, certain improved equivalents of which have been described at the time in the French Pat. No. 72 06 315, as well, besides, as in the first certificate of addition which is attached to it.

The diagram in FIG. 8 corresponds, moreover, with the structure of FIG. 3. In fact, referring to that Figure and FIGS. 5 to 7, it is to be observed that the duct 37a is indeed permanently in communication with the pipe 19 (through the recess 41), whereas the duct 38 is in communication with the pipe 19 only during the period of rotation of the hub 39 with respect to the sleeve 29, which corresponds with the communication of the duct 38a with the recess 42. Similarly, this duct 38 is in com munication with the pipe 20 only during the period of the said rotation which corresponds with communication of the duct 38b with the recess 43.

The lugs 24 and 31 being offset with respect to the axis of rotation 25 of the plates 23 and 26, the straightline vibratory motion of the piston rod 33 gives rise to rotational vibrations of the plate 23 with respect to the plate 26. Consequently, the plate 26 being driven in continuous rotation (when the tool is in service) by the output shaft 27 of the motor in housing 5, the plate 23 is driven with a rotational motion which is the resultant of the continuous rotational motion of the plate 26 and the vibratory motion generated by the jack 32. The auger 11 is itself subjected to the same rotational and vibratory motion as the plate 23 to which it is connected rigidly by the shafts l6 and 12. The ground is therefore attacked by the blade of the auger 11 in a succession of blows which facilitate the disintegration of the ground and consequently the penetration of the auger into the ground is facilitated.

The auger may equally be subjected to longitudinal vibratory motion which also facilitates its penetration. Finally, the vibrations generated can have forward and return paths of different durations and forms.

Instead of the regulator consisting of the sleeve 29 and the hub 39, an external regulator may be adopted independent of the continuous rotational motion generated by the motor in housing 5.

Finally, by modifying the number of apertures of each type 41, 42 and 43 it is quite obvious to those skilled in the art that the frequency of the vibrations generated can be varied.

For the rest, the invention is not limited to the description which has been given of it, but on the contrary covers all the variants upon it which could be applied to it without departing from its scope or its spirit.

We claim:

1. An excavator tool comprising a support, an auger mounted rotatably with respect to the said support, a motor for driving the auger in rotation, linked between the support and the auger, and a vibration-generator interposed between the support and the auger which in operation generates a vibratory rotational motion coaxial with the main rotation of the auger, the generator comprising a fluid-operable ram having at least one working chamber, and means for placing the chamber alternately in communication with a source of fluid under pressure and with a discharge tank, the ram being linked between one of the relatively movable elements of the motor, the frame or the output shaft, which is movable with respect to the support, and the shaft of the auger, and eccentrically with respect to at least one of these parts comprising the movable ele ment of the motor and the shaft of the auger.

2. A tool as in claim 1, wherein the communication means includes a regulator operable to alternately connect the chamber to the source and the tank to the regulator, comprising a central hub linked to the movable element of the motor and received in a sleeve fixed with respect to the support of the tool and which includes, when the ram has one working chamber, two

apertures arranged in the inner face of the sleeve connected, one to the source of fluid under pressure, and the other to the discharge tank, and a duct in the hub which communicates in the course of one revolution of the hub with respect to the sleeve. during one portion 5 nently into the one aperture and is connected to the said second working chamber. 

1. An excavator tool comprising a support, an auger mounted rotatably with respect to the said support, a motor for driving the auger in rotation, linked between the support and the auger, and a vibration-generator interposed between the support and the auger which in operation generates a vibratory rotational motion coaxial with the main rotation of the auger, the generator comprising a fluid-operable ram having at least one working chamber, and means for placing the chamber alternately in communication with a source of fluid under pressure and with a discharge tank, the ram being linked between one of the relatively movable elements of the motor, the frame or the output shaft, which is movable with respect to the support, and the shaft of the auger, and eccentrically with respect to at least one of these parts comprising the movable element of the motor and the shaft of the auger.
 2. A tool as in claim 1, wherein the communication means includes a regulator operable to alternately connect the chamber to the source and the tank to the regulator, comprising a central hub linked to the movable element of the motor and received in a sleeve fixed with respect to the support of the tool and which includes, when the ram has one working chamber, two apertures arranged in the inner face of the sleeve connected, one to the source of fluid under pressure, and the other to the discharge tank, and a duct in the hub which communicates in the course of one revolution of the hub with respect to the sleeve, during one portion of this rotation with the one aperture and during another portion of the said rotation with the other aperture, and is connected to the said working chamber.
 3. A tool as in claim 2, in which the ram is a double-acting ram and has a second working chamber, another duct being bored into the hub, which opens permanently into the one aperture and is connected to the said second working chamber. 